luks2 + integrity + discard

Hello,

I'm quite puzzled about the, apparently,
missing support of discard (or trim) in
case of encryption with integrity.

From what I understand, which might be
very wrong, both the encryption layer
and dm-integrity should support discard.

Reading the documentation does not really,
at least for me, clarify what is the
reason why it should not be possible to
have encryption + integrity + discard.

On the other hand, in case of integrity
under the raid, with lvm and luks2 on
top, it seems possible to have discard.

Can someone provide some clarification
on this?

Thanks a lot in advance,

bye,

-- 

piergiorgio